Reversible rotary liquid pump



Nov. 18 1941- e. A. MUELLER, JR., EI'AL- 2,2

REVERSIBLE ROTARY LIQUID PUMP Filed March 7, 194 4 Sheets-Sheet 1 /NVENTOR5 George AMue/lerj; Fa/phJHoo/(er Jbhn Wflnderson Nov. 18, 1941.

G. A. MUELLER, JR, ETAL REVERSIBLE ROTARY LIQUID PUMP" Filed March '7, 1940 4 Sheets-Sheet? lNVfNTOFI'S GeorqeAMuel/egjn 0/11 Hoqker B Jbhn Wflnaerson Z0 A omvzy Nov. 18, 1941.

G. A. MUELLER, JR., ETAL REVERSIBLE ROTARY LIQUID PUMP 4 Sheets-She et 5 Filed March 7, 1940 I INVENTORS George HMu e//e/: '1; hJl-loo/cer,

Illa

Pa p Jbhn W. Anderson .37 I Z XZNEY Nov. 18, '1941- G. A. MUELLER, JR... ETAL 2,253,548

REVERSIBLE ROTARY LIQUID PUMP Filed March '7, 1940 4 Sheets-Sheet 4 FIG.6.-

FIG. 5.

IN VENTORS Ge 0 rye r9, Mu'l/egjr: Ralph IHoo/(el Jb/vn W. Anderson Patented Nov. is, 1941 UNITED STATES PATENT OFFICE 2,263,548 REVERSIBLE ROTARY LIQUID PUMP George A. Mueller, Jr., Ralph J. Hooker, and John W. Anderson, Auburn, N. Y., assignors to American Locomotive Company, New York, N. Y., a corporation of New York Application March 7, 1940, Serial No. 322,726

2 Claims.

Fig. is a section on the line v-'-v of Fig. 1, with certain parts removed and other parts shown in full showing the valve in its uppermost. position;

adaptable for many varied uses, it is especially applicable for pumping liquid through a closed ble characteristic, and which is advantageously coupled with the pump as a drive therefor to render the pump rotation reversible with reversal of the engine. The present principal known use for the apparatus is in connection with a Diesel engine such as a marine engine where reversal of the propeller shaft is an essential characteristic. The apparatus, as shown in the present instance in its preferred embodiment, is especially adapted for such use and it will be understood that the driven shaft of the pump is connected with a driving shaft forming part of the engine which driving shaft is reversible with reversal of the propeller shaft (either by reversal of the engine or otherwise, according to usual practice) and which in turn reverses the direction of rotation of the pump. When the apparatus is so used the lubricating oil ordinarily flows througha closed system containing a sump from which the liquid is drawn and to which the liquid returns for repeated use after it has made a lubricating cycle, and the present apparatus is designed for such a closed system, the pump being instrumental in circulating the liquid through the system which includes the apparatus of the present invention.

Referring to the drawings forming part of this application, Figure 1 is a plan view ofan apparatus embodying the present invention, the

discharge pipe'being broken away; Fig. 2 is asection on the line IIII of Fig. 1, with various parts shown in full; Fig. 3 is a view, similar to Fig. 1, showing a modified apparatus having two pumping units, with the pipe connections removed; Fig. 4 is a section on the line IV-IV of Fig. 3, with various of the parts shown in full;

Fig. 6 is a, view similar to Fig. 5 showing the valve in its lowermost position; Fig. '7 is a fragmental section on the line VII-VII of Fig. 5, the valve being omitted; Fig. 8 is a fragmental section on the line VIII-VIII of Fig. 5, the alve and spring being omitted; Fig. 9 is a section on the line IX I X of Fig. 8, the valve and springs being shown in valve intermediate position; Fig. 10 is a section on the line XX of Fig. 3, parts being shown in full; and Fig. 11, at the left, is

an end view, and at the right, a section on the line XIXI of Fig. 2, with parts removed.

While the invention is not confined to any' particular type of reversible rotary liquid pump it is shown in its preferred embodiment with a pump of the intermeshing gear type.

Figs. 1 and 2 show the apparatus as involving but a single pump (best shown in Figs. 2, 5 and 6) involving two interfitting gear wheels or pumping elements I and 2. The pump is housed within a casing, indicated generally by the reference numeral 3, which comprises a body portion 4 provided with a front integral wall 5, and a rear wall 6 detachable from the body portion. A gear casing, indicated generally by thereferenee numeral 1, is disposed adjacent the pump casing at the rear thereof, and is open at its front wall opposite the wall 6 and secured thereto by studs and bolts 8. The casing I is provided with a flanged top wall 9 for bolting the present apparatus to the. engine or the like, with which the present apparatus is to be employed and in suitable association to a reversible part of such engine, etc. to effect driving of the pump. To this end the shaft of a gear wheel I0 is mounted in blocks ll secured to the top wall 9, the wheel extending downwardly-into the casing 'l through an opening in the top wall. This wheel is for engagement with another gear wheel which is mounted on a shaft and which forms part of and is reversible with the engine (not shown) with which the present apparatus is employed.

The pump gear wheel I is integrally formed on a shaft 12 mounted in through openings provided in the walls 5 and 6, the shaft extending The.

a through opening provided in the wall and in an opening in the wall 6 that extends but part way through this wall. A plate I5 is disposed in...

engagement with the outer face of the wall 5. The wall 6, body portion 4 and plate |5 are secured together by bolts l8.

The pump gear wheels I and 2 fit between the walls 5 and B with a working clearance and similarly havea. working clearance with a transverse partition wall forming part of the body portion 4, through which the bolts l6 pass. The

outer wall l8 of the casing body portion 4 is opening or passageway l9 extending from front to back at one side thereof (the left side as viewed in Fig. 1 and best seen in Figs. 5 and 6). A post 20 is disposed midway of this opening through which one of the bolts l6 passes for better securing the parts of the casing 3 together. At the side opposite the passageway IS the top and bottom portions of the partition wall H are spaced to provide a large opening or passageway.

2| comparable in size with the passageway I9 and extending laterally outwardly to form respectively walls 22 and 23 combining with the adjacent walls to provide a throat 24. The passageway 2| is provided with centrally disposed narrow ribs or supporting wall portions 25 (only one being shown) spaced to provide an opening 26 connecting the top and bottom portions of the passageway 2|. At the inner ends of the wall portions 25, there is a post 21 similar to the post 20 through which one of the bolts 16 passes.

The passageways 2| and I9 are respectively for ingress and egress of the liquid to and from the pump when the pump is rotating in the direction as indicated by the arrows in 5, which, for convenience, will be termed ahead direction or rotation. And reversely the openings I9 and 2| are respectively for ingress and egress of the liquid to and from the pump when the pump is rotating in the opposite direction to that of Fig. 5, and as indicated by the arrows of Fig. 6, which, for convenience, will be termed astern direction or rotation. These terms ahead and astern are employed to correspond to the direction of rotation of a propeller shaft of amarine engine where the invention is especially applicable. coupling the apparatus with the engine would, in practice, determine the direction of rotation of the pump, it only being necessary that the proper directional flow of the oil to'and from the apparatus be effected.

The liquid is carried by the pump gear wheels frcm one opening or passageway to the other around the inner faces of the upper and lower portions of the partition wall H. The liquid, as thus carried by the pump, travels in one direction for ahead movement and in the opposite direction for astern movement.

An important feature of the invention is that while the liquid is fed to the pump and discharged therefrom in opposite directions, requiring passing through the pump casing in opposite directions, one for ahead movement and the other for astern movement, nevertheless the flow of liquid to and from the apparatus is always in However the manner of -gral.

one parts together.

the same direction. This is a necessary require ment in a pump for pumping liquid through a lubricating system of a reversible engine or other apparatus, and this uni-flow direction of the liquid therefore must be maintained even though the engine or other machine to which the apparatus is applied is reversible.

The apparatus of the present invention further comprises a valve casing, indicated generally by the reference numeral 28, which casing comprises a body portion 29 having a wall 30 provided with an upper head 3| and a lower head 32, each studded to the wall 30. The wall 30 has an upper cylindrically-faced portion 33, a lower similar portion 34, an intermediate inner cylindricallyfaced portion 35, a wall portion 36 disposed between the portions 33 and 35, spaced therefrom, and provided with an inner cylindrical face, and

another wall portion 31 disposed between the portions 34 and 35, spaced therefrom, and provided with an inner cylindrical face. The several inner cylindrical faces are in alignment and provide jointly a cylinder or chamber 33 for the piston valve, later to be described. The aforesaid spaces between the wall portions provide four ports as will later more fully appear.

The valve casing28 and the pump casing 3 are shown as forming anintegral structure. The former is shown disposed adjacent the latter at the side thereof containing the passageway 2|.

.. These two casings merge into a common wall portion in which are portions of the aforesaid four ports. The type no part of the present invention. For instance, the casings need not necessarily be made inte- They may be made separate and connected together in any suitable manner. Sufiice it to say that the valve-controlled ports and various other features of the valve casing have communication with the pump casing even though this may be accomplished through an integral structure, a composite bolted structure or through structures involving piping connecting the vari- For this reason, regardless of the specific structure, the two casings may be considered as a single casing in the broad sense of the word. This casing is divided into two compartments by a ported wall, one compartment housing the pump and the other compartment housing the piston valve.

The partition wall divides the pump casing into an inner chamber 39 which contains the pump gear wheels and which opens to the passageway 2| affording communication with the valve casing, and an outer chamber 40, the two chambers communicating through the passageway |9 for affordiii the inner chamberrto the valvecasing through the outer chamber, as will presently more fully appear. The outer chamber to this end is provided with an upper portion 4| and a lower portion 42.

To afford the aforesaid communications with the valve casing'the wall portion 33 is formed integral with the upper portion of the pump casing outer wall I8 and the wall portion 36 is formed integral with the wall 22. Between the adjacent ends of the wall portions 33 and 36, the upper chamber portion 4| is open to provide an upper port a. In like manner the wall portion 34 is formed integral with the lower portion of the pump casing outer wall l8 and the wall portion of easing or casings forms.

further communication of the lower chamber portion 42 is open to provide a lower port b. The wall portion 35 is formed integral with the ribsor supporting wall portions 25. Between the adjacent ends of the wall portions 35 and 36 the passageway 21 is open to provide an upper intermediate port 0. Likewise between the adjacent ends of the wall portions 35 and 31 the passageway 2| is open to provide a lower intermediate port d.

These four ports a, b; c and (1 provide the aforesaid communications between the pump chambers 39 and 48 and the valve casing and are controlled by a single valve later to be described.

The wall 38 is enlarged from the upper edge of the port a. to the lower edge of the port circumferentially by the wall portion 43 providing a space or chamber 44 exterior to the valve cylinder 38 within the valve casing. The chamber 44 is divided by diametrically opposite wall portions-into two parts, as will later appear, and

the inner part is divided into upper and lower sections by the wall 22. These sections are open to the valve cylinder through the ports a and c, which extendto the just-mentioned opposite wall portions and, are, exteriorly of the valve cylinder, open, the uppersection to the chamber portion'4l and the lower section to the passageway 2| at the upper part thereof. Similarly the wall 30 is enlarged from the upper edge of the port (1 to the lower edgeof the port 1; circumferentially by the wall portion 45 providing a space or chamber 46 exterior to the valve cylinder 38 within the valv casing. The chamber 46 is divided by diametrically opposite wall portions into two parts, as will later appear, and the inner part is'divided into upper and lower sections by the wall 23. These sections are open to the valve cylinder through the ports d and b, which extend tot-he just-mentioned opposite wall portions and,

are exteriorly of the valve cylinder, open, the lower section to the chamber portion 42 and the upper section to the passageway 2| at the lower part thereof.

The wall portions 43 and 45 (best shown in Figs. 7 and 8) at the back of the valve casing turn inwardly to provide respectively. wall portions 41 and 48 which connect respectively with the wall portions 38 and 31 and extend from the lower edge of the wall portion 33 to the upper edge of the wall portion 34, extendinginwardly between the ports to form part of\ the valve cylinder. 7

At the front of the valve casing and. opposite the wall portions 41 and 48 the wall 38 is thickened from top to bottom to provide a solid portion 49- which extends outwardly from the 'portions 33, 35 and 34, and which extends inwardly from the'portions 43 and 45 connecting these two portions '43 and 45.respectively with the portions 36 and 31, and which extends respectively across the ports H and d-b to the inner face of the valve cylinder to form parts thereof. The solid portion 49 in its passage through the chambers 44 and 46 thus provides respective wall portions 50 and similar to the wall portions 41 and 48. The wall portions 41 and 50 divide the chamber 44 into an inner' portion 52 I at the side of the valve cylinder adjacent the pump casing, and an outer portion 53 at the opposite side of the valve cylinder. Likewise the wall portions 48 and 5| divide the chamber The outer portion 55 is provided with an inlet or suction opening 56, flanged to engage the flange of a pipe coupling 51, and the coupling 51 is flanged at its opposite end to engage the flange of a pipe 58 which is provided with a check valve 59. The check valve is not required for the proper functioning of the apparatus but is desirable to prevent flow from the -valve casing through the inlet or suction opening in case the apparatus should temporarily fail to function, as will later more fully appear. The outer portion 53 is providedwith an outlet or discharge opening 60, flanged to engage the flange of a pipe coupling BI, and the coupling BI is flanged at its opposite end (not shown) to receive the flange of a pipe (not shown). The respective engaging flanges are bolted together in the usual manner. By a different setting of the valve casing heads 3|.an'd 32 from that shown in the drawings the opening 68 will serve as the inlet or suction opening and the opening 56 will then serve as the outlet or discharge opening, as will later more fully appear. With such a change the check valve 59, if employed, will obviously be placed in the other pipe.

It will be understood that the couplings and pipes leading from the inlet and outlet openings of the valve casing, as well as the apparatus, are included in the fiow circuit leading to and from the Diesel engine or other machine, or more properly that portion thereof that is to be lubricated. The flow circuit will usually include a sump for containing the supply of lubricating oil and the inlet opening 56 will be connected through piping therefrom to the sump and the lubricating oil therein whereby the pump is supplied with lubricating oil flowing from the sump through the piping to the inlet opening 56'and therefrom through the valve'casing to the pump casing.

The outlet opening 68 will be connected through piping therefrom to the part of the engine or other machine to be lubricated and other piping forming part of the flow circuit will lead therefrom to return the lubricatingliquid that has been used to the sump. Obviously this part of the piping need not enter the liquid in the sump. It may terminate above the level of the liquid in the sump, it only being necessary that it discharge into the sump, and to this extent in such event the flow circuit would not be strictly closed. This however, is not a part of the present invention and only illustrates a possible use therefor. Furthermore it is not intended to limit the apparatus solely for pumping lubricating oil. It may have other uses.

The liquid is pumped, when the pump is in operation, to maintain a continuous flow or circulation of the liquid through the system during the operation of the engine or other machine.

The pump pumps the liquid from the valve casing. The pump pumps the liquid to produce the flow and the piston valve cooperating with the ports a, b, c and 11 operates to maintain a unidirectional flow always through the inlet opening 56 to the pump casing and out of the pump casing to the. outlet opening 60. While the pump 46 into an inner portion 54 at the side of the maintains the flow it will be understood that part of this flow will be by gravity, depending up on the relative heights of the various parts included in the flow system.

In the case of a marine Diesel engine, for illustration, in addition \to supplying lubricating oil to the engine it is usually desirable to also supply lubricating oil to the clutch between the ited to a single pump and valve unit but may include other units according to the use to be made of the invention. Therefore according to the above illustration two units would be employed, one for the engine and the other for the clutch, and Figs. 3, 4 and illustrate a modification of the invention covering two units which will later be described.

Returning to the single unit embodiment, the piston valve is indicated generally by the reference numeral 62. It is of somewhat skeleton formation and has a cylindrical broken outer face 63 which engages the face of the cylinder 38 to provide a sliding fit in an axial direction therewith for control of the port a, b, c and d.

In the present instance he valve is provided for three adjustments, that is to say three positions, namely an upper position, shown in Fig. 5, opening the ports d and a, and closing the ports band 0, a lower position, shown in Fig. 6, opening the ports b and c, and closing the ports d and a, and an intermediate position, shown in Fig. 9 but best shown in Fig. 10, (of the two unit embodiment), closing all the four ports.

The valve 62 is preferably an integral structure. It comprises a middle body portion 64, which support three sections or portions 65, 66

and 61, each providing a portion of the valve cylindrical outer face 63. The portion 65 is in the form of a hollow cylinder open at its upper end and closed at its lower end by the wall 68 integrally formed with the body portion 64 at the upper end thereof. This portion 65 has an outer cylindrical face 69 which controls the port a. The portion 66 is similar to the portion 65 but reversed in direction thereby being open at its lower end and closed at its upper end by the wall 10 integrally formed with the body portion 64 at the lower end thereof. This portion 66 has an outer cylindrical face II which controls the port b. The portion 61 is disposed centrally between theportion 65 and 66 and is integrally connected to the body portion 64 through the centrally disposed hub 12. This portion 6I has an outer cylindrical face 13 which controls the ports 0 and d.

The ports a, b, c and d, which are valve cylinder ports connecting thecylinder with the pump casing, are preferably of the same length or height and are preferably of the same width; the width being large in comparison to the length. to provide/large port openings. The ports a and c terminate at the wall portions 41 and (see Fig. 7 for the port 0), and the ports b and d terminate at the wall portions 48 and 5| (see Fig. 8 for th port 1)). The ports thu extend substantially half way around the valve cylinder and v have spaced therefrom the inner portion of the wall 43 (for ports a and c) which mergesinto the pump casing and the inner portion of the wall 45 (for ports I) and d) which likewise merges into the pump casing. The aforesaid merging is more properly into the common wall portion between the pump and valve casings. From the foregoingit will be seen that the chamber inner portions? 52 and 54 are exterior to and extend half way around the valve cylinder and their sections are adjacent respectively to the ports a'c and db. The chamber outer portions 53 and 55 are exterior to and extend half way around the valve cylinder and are adjacent respectively to other valve cylinder ports a'-c and reach the pump from the inlet opening 66 and y can only reach the discharge opening 60 through the. valve as will later more fully appear.

- The lower end of the portion 65 is spaced from the upper end of the portion 61 to provide a valve port e, and likewise the upper end of the portion 65 is spaced from the lower end of the portion 61 to provide a valve port f. Thus the valve has two ports preferably of a length or height equal to the ports a, b, c and d but extending entirely around the valve.

The body portion 64 is made relatively small in cross section and the hub 12 is made relatively thin providing a skeleton formation for the valve whereby a valve chamber 14 extending entirely around the valve is provided for the valve port e, and another valve chamber 15 likevided for the valve port I.

The valve port I, when the valve hasbeen adjusted to raised position as shown in Fig. 5, opens the port d to theinlet or suction opening 56, the cylindrical face II at the same time closing the port 1). Likewise in this position of the time closing the port (1. Likewise in this position 'of the valve, the valve port 2 opens the port 0 to the outlet or discharge opening 60, the

cylindrical face 69 at the same time closingthe port a. v Thus it will "be noted that during these two adjustments the valve ports e and I are always active but only twoof the ports a, b, c and d are open for these two valve adjustments.

In each valve adjustment the liquid from the inlet or suction opening 56 to reach the pump casing must pass through the valve chamber 15 and likewise the liquid to enter the outlet or discharge opening 60 must pass through the valve chamber 14, This is necessary on account of the wall portions 48 and 5| dividing the chamber 46 into the two portions 54 and 55, and the wall portions 41 and 50 dividing the chamber 44 into the two portions 52 and 53. In other words the liquid to get from one side of the valve casing to the other must pass. through the valve chambers.

It will thus be seen from the foregoing that for the rotation of the pump gear wheels as shown by the arrows in Fig. 5, which has been previously considered rotation for ahead movement, the valve is in raised position. The liquid enters the port d and travels through the passageway. 2| toward the left to the left side of the pump. It is discharged by the pump through the passageway l9 and travels throughv the portion 4| to the port a.

It will further be seen that for the opposite rotation of the pump gear wheels as shown by the arrows in Fig. 6, which has been previously considered rotation for astern movement, the valve is in lowered'position. The liquid enters the port 1), travels through the portion 42, and from the portion 42 it travels through the passageway I9 toward the right to the right side of the pump. It is discharged by the pump through the passageway 2| to the port 0.

From the foregoing it will bev seen that for either rotation of the pump gear wheels the liquid enters the apparatus through the inlet or suction opening 56 and leaves the apparatus through the outlet or discharge opening 60. The only difference between ahead and astern movements is that for ahead movement the liquid enters the pump from the right side thereof and that the ports (1 and a are the active ports, and that for astern movement the liquid enters the pump from the .left side thereof and that the ports b and c are the active ports. Furthermore the valve port I connects the pump casing with the inlet or suction opening 56 at both positions other types of valves and arrangements and number of ports may be used, suitable to attain the aforesaid object of the invention.

The piston valve 62 cooperates with the valve casing 28 to provide an upper fluid chamber16 of variable capacity, and a lower fluid chamber 11 also of variable capacity. Within the chamber 16 is a compressible coil spring 18 abutting at its upper end the head 31 and at its lower end the 'wall 68. A similar spring 19 is disposed with-'- in the chamber 11 abutting at its lower end the head 32 and. at its upper end the wall 10. These springs serve to stabilize or steady the adjusting movements of the piston valve but' are primarily for returning the piston valve from either of its raised or lowered active positions, which are its extreme positions, to its aforesaid intermediate inactive position as shown in Fig, 9, in which'position all the ports are closed, as best shown in Fig. 10, the ports being provided with a suitable amount of overlap in this position of the piston valve as clearly shown in Fig. 10. In this intermediate position of the valve the springs are but slightly compressed but sufiiciently so to insure the maintaining of the piston valve in this all-port-closed position.

The piston valve is automatically actuated from its intermediate position to either of its extreme positions and held in these extreme positions by liquid pressure due to the action of the pump. Before describing the structural features and their manner of operation to accomplish this it should be noted that in the upper position of the piston valve, as shown in Fig. 5, the upper spring 18 is further compressed and that the lower.

due to the operation of the pump, the direction of the piston valves movement being dependent upon the direction of rotation of the pump gear wheels; as will later be explained. Also, as will later be explained, upon reversal of the rotation of the pump the piston valve will automatically move from its then adjusted extreme position to its intermediate all-port-closed position, resembling its movement when the pump comes to rest, and from this intermediate position it will immediately move to its opposite extreme position responsive to the reversal of the rotation of the On the lower end of the wall portion 36 within the-inner portion 52 of the chamber 44 and between the wall portions 41 and 50, that is to say on the pump side of the valve casing; is an outwardly directed transverse wall portion 80 of the wall 22 and which divides the portion 52 into two parts, thereby separating ports a and 0. At the upper end of the wall portion 31 is a similar wall portion Bl of the wall 23 which divides the portion 54 into two parts, thereby separating ports b and d. The ports b and d are not separated nor are the ports a and c separated. This is because the portions 55 and 53 are merely chambers respectively for the inlet opening 56 and the outlet opening -60, the former opening supplying liquid to either the port b or d, depending upon the position of the piston valve, and the latter simultaneously receiving liquid respectively from the port 0 or a.

The portions 55 and 53 are however separated by the wall portion 35 and the branches of the wall portions and 43 extending therefrom, the

branch of the wall portion 45 extending to the walls 48 and 5| and the branch of the wall portion 43 extending to the walls 41 and 50. The' The movement of thepiston valve from its all- I port-closed position to its extreme positions is 84 active and the other rendering the passageway piston valve is in its intermediate position. In

compressed and the upper spring is slightly expanded.

As is obvious, when there is no liquid pressure in the apparatus the energy of the further compressed springs 18 and 19 (as the case may be for the respective positions of the piston valve) will operate to automatically return the piston valve to its intermediate position. This occurs when the rotation of the pump ceases. Therefore when the pump is at rest the piston valve is always in its all-port-closed position. Accordingly when the pump starts to rotate the piston valve is initially at all-po'rt-closed position, and it will be adjusted automatically by fluid pressure dependent upon the liquid pressure produced by the rotating pump, and which of the extreme positions it will assume is dependent upon the direction of rotation of the pump.

The following means are provided to effect accomplishment of these valve movements. The

solid portion 49 is availed of and a bore 82 ex-' tending from end to' end thereof is provided therein. A transverse, passageway 83 divides the bore 82 into an upper passageway 84 and a lower passageway 85, both opening into passageway 83. The heads 3| and 32, as aforesaid, are designed for two settings, one rendering the passageway 85 active, as will later more fully appear. The drawings show the passageway 84 active and the passageway 85 dead. The foregoing description of the apparatus however equally applies as to structural features whichever passageway 84' or communication. at all times between the passageciently thick to provide for a lower passageway 86 and an upper passageway 81 to be formed therein. The same remarks here apply as have been previously made regarding the heads 3| and 32 except that in the present setting of the heads 3| and 32 the passageway 88 is the active passageway and the passageway 81 is dead. The pas sageway '86 at its upper end has a mouth 83 opening into the lower part or the chamber portion 54 thereby affording communication at all times between the passageway 88 and the lower portion 42 of the chamber 40. Similarly the passageway 81 at its lower end is provided with a mouth 89 opening into the upper part of the chamber portion 52 thereby afiording communication at all times between the passageway 81 and the upper portion 4| of the chamber 49.

The head 3| is provided with a circular flange 90 against which the piston valve seats when in its raised position and the head 32 has a similar flange 9| against which the piston valve seats when in its lowered position. The head 3| is provided with a recess 92 registering with the chamber 18 and passageway 84 thereby bringing the upper fluid chamber 18 into communica tion with the passageway84. The head 32 has a similar recess 93 aiiording communication between the chamber 11 and passageway 88. The passageway 85 is closed at its lower end by the head 32 and the passageway 81 is closed at its upper end by the head 3|. The passageways 85 and 81 are thus rendered inactive.

The operation of the apparatus is as follows:

When the pump is at rest the liquid in the apparatus is under atmospheric pressure; at least there is no differential pressure of the liquid filling the several parts of the apparatus and the piston valve is in all-port-closed position as shown in Figs. 9 and 10. If the pump is rotated from this; position of rest in the direction shown by the arrows in Fig. (ahead movement), the inlet opening 58 and the outlet opening 80 being closed, the pump will operate to draw the liquid from the chamber 18 through the parts 92, 84, 83, 52 (at the lower part thereof) and 2|. It will at the same time force the liquid to the chamber I1 through the parts I9, 42, 54 (at the lower part thereof), 88, 88 and 93. produce adiflferential liquid pressure on the opposite sides of the piston valve, the predominating pressure being in the chamber 'I'I. The piston ,valve will begin its upward movement and initially open the ports a and (1. At this point the pump will begin to take liquid from the inlet opening 58 and discharge it through the outlet opening 80. The valve will continue its movement upward to its extreme position fully open-- ing the ports a and d, the ports 0 and b remaining closed. The piston valve will remain in this position for the reason that the differential pressure is maintained during this ahead'movement. This. differential liquid pressure compresses the spring 18, the spring 19 being substantially neutral. When the pump is stopped the difierential pressure ceases, that is tosay the liquid pressure in the apparatus is reduced to atmospheric pressure or to uniform pressure at least insofar as its action on the piston valve is concerned. The spring 18 thereupon reacts and consequently the piston valveis lowered to its intermediate or all-port-vclosed position. The spring then acts to yieldingly resist valve movement from this position.

If the pump is rotated rest in the direction shown by; the arrows in Fig. 6 (astern movement), the pump will operate to draw the liquid from the chamber 11 and disfrom this position of pump. In the extreme position of the piston This willi to all-port-closed position when the pump stops,

is similar to that previously described with reference to Fig. 5. a

When the rotation of the pump is reversed, say for instance from its rotation as shown by the arrows in Fig. 5 to its rotation as shown by the arrows in Fig. 6, the piston valve (which is then in its raised position) immediately moves to its intermediate all-port-closecl position, and from this intermediate position moves to its opposite extreme position as shown in Fig. 6 in-the manner previously described. Thus the apparatus in both extreme positions of the piston valve takes the liquid from the inlet or suction opening .58 and discharges it through the outlet or discharge opening 88 thereby insuring a uni-directional flow of the liquid from the apparatus through the system for either direction of rotation of the valve shown in Fig. 5, the liquid enters the pump inner chamber 39 and the pump'from the right side thereof, and in the extreme position of the piston valve as shown in Fig. 6, the liquid enters the pump inner chamber 39 and the pump from,

the left side thereof.

If the head 3| is turned about its axis to bring the recess 92- in register with the passageway 81 thereby simultaneously blocking off the passageway 84, and the head 32 is similarly turned. toregister the recess 93 with the passageway 85 thereby simultaneously blocking ofi the passageway 88, the operation is similar to that already.

described but the movement of the piston valve is reversed. The opening 80 will then be the inlet or suction opening and the opening 58 will be the outlet or discharge opening. Consequently the flow through the system from and to the apparatus will be in the reverse direction.

To insure proper setting of the heads 3| and 32 they are made of a shap more or less triangular and seat upon a similarly shaped face of the pump casing. They are secured to'the casing by studs 94 uniformly spaced, two studs being provided for each side of the triangle.

The recess in the head (92 or 93 as the case may be) is denoted from the outer face of the head by an indicator, which in the present instance is an arrow 95, cast or otherwise marked on the head. j

The recesses are disposed opposite one of the vertexesof the triangle of the heads and one of the vertexes of the triangle of the seats is disposed at the front of the apparatus in register with the bore 82 (passageways 84-85) The passageways 88 and 81, which arein alignment, are

- on the head 3| points toward the recess 92,.and

the indicator 95 (dotted lines) on the head 32 points toward the recess 93. This is the setting of the heads forthe operation of the apparatus as shown in Figs. 5 and 6. 'To move the heads to their other settings all that is necessary is to rotate the head 3| in a clockwise direction, as viewed in Fig. 1, and the head 32 120 in the reverse direction, the heads of course being first freed from and finallysecured to their respective seats. This provides a simple and ready means of selecting which of the openings 58 or 60 shall be the inlet or suction opening and the other the outlet or discharge opening, no other changes in the apparatus being necessary to provide for this, except changing the check valve seer employed) to the other pipe, as already mentioned. The' head adjustment may be of particular advantage where more than one pumping unit is employed, that.is to say where more than one flow circuit is handled by the apparatus, as it provides for a selection of flow to and from the apparatus for each pumping unit even though the pumps of the units are driven by the same shaft and consequently in the same direction.

Figs. 3, 4 and show such a multiple unit apparatus. While in this embodiment only two pumping units are employed it will be under-' stood that it is contemplated as within the in-'- vention to use other units ere desired. This may be done, as will be seen, in an obvious manner without changing the basic principle or operation. There are but few structural differences between the single pumping unit apparatus and multiple pumping 'unit apparatus. Therefore where reference is made to similar parts similar numerals are employed with accents added. It is therefore deemed unnecessary, as it would be a mere, repetition to describe the operation or structure except as to the structural differences.

Where two pumping units are employed they are placed side by side, one unit being disposed outwardly of the other, and the inwardly disposed unit being adjacent the gear casing. Bolts ii are employed similar to the bolts [6 but longer for holding the plate l5, pump casings and gear casings together. f

The pumping units are separate from each other except as to the pump gear wheel shafts, which are common to both units, and one plate l5 serves for both units, the inner unit requiring no separate plate as is obvious. This brings the rear face of the outer pump casing into engagement with the front face of the inner pump casing. The front wall 5" of the inner pump piston valve as shown in Fig. 5. Upon reversal of the rotation of the pump gear wheels from that shown in Fig. 5 to that shown in Fig. 6, if the. piston valve, on account of being stuck or for some other reason, fails to immediately move to its intermediate position preparatory to moving to its position shown in Fig. 6, the check valve 59 will serve to correct this and the piston valve 58. Therefore a liquid pressure is provided in passageway 2| which is open to the chamber 16 through the parts as aforesaid, namely 83, 84 and 92. This liquid pressure therefore directly acts upon the piston valve at the wall 68 thereof and forces the piston valve to its intermediate or all-po :t-closed position, whereupon the action of the apparatus becomes normal moving the piscasing thus serves as the rear Wall for the outer pump casing similar to the wall 6' which serves as the rear wall for the inner pump casing. The pump gear wheel 96 of the inner pumping .unit has its integral shaft 91 extending through the pump casing of the outer pumping unit and journalled into its wall 5'. The pump gear wheel 98 of the outer pumping unit is keyed on the shaft 91. The pump gear wheel 99 of the inner pumping unit is driven by the gear'wheel 96 and the pump gear wheel Hill of the outer pumping unit is driven by the gear wheel 98. Gear wheels'99 and I00 are freely mounted on a common shaft llll which extends through both pump casings being mounted at its inner end in the wall 6' and at its outer end in the wall 5 of the outer pumping unit and passing through the wall 5" of the inner pumping unit. It will thus be seen that the pumps of the pumping units are driven by a single gear wheel l3. They therefore rotate in the same direction and are reversed simultane-' ously when the gear wheel I3 is reversed.

The apparatus of the present invention is particularly simple as to structure and reliable'as tooperation. Nevertheless should the piston valve faihto move upon reversal of the pump, provision is made to meet such a failure either when the piston valve is in its raised position, as shown in Fig. 5, or in'its lowered position, as shown in Fig. 6. A single illustration of such provision will suflice. I

Consider for illustration the position of the ton valve to its lowered. position as shown in Fig.6.

While there have been hereinbefore described approved embodiments of this invention, it will be understood that many and various changes and modifications in form, arrangement of parts therein, one side of said pump being an inlet side for one direction of rotation and a discharge side for the other direction of rotation of said pump,

and the other side of said pump simultaneously respectively being a discharge and an inlet side;

a valve chamber; and a piston valve-in said chamber axially movable to two opposite positions, said chamber providing with said valve at each end thereof a space for valve-operating liquid and said 'spaces being in communication with said casing,

each at'one of said sides of said pump to effect movement of said valve by pump-produced liquid pressure to one or the other of its said positions dependently responsive to the direction of rotation of said pump, said valve being moved in a direction from, and by the liquid in, the space in communication with the then discharge side of ber further having an admission orifice transversely opposite said inlet ports and a discharge orifice transversely opposite said outlet ports, said valve having a port for controllably opening said inlet ports and opening transversely through said valve at either of said inlet port openings to said admission orifice, said valve further having another port for controllably opening said outlet ports and opening transversely through said valve charge orifice, said two valve ports :being operatively independent of said two end spaces, said four'chamber ports being suitably positioned in two alternately disposed chamber ports and closing of the othertwo chamber ports at one of said positions of said valve, and opening of theother two alternately disposed chamber ports and closing of the'remaining two chamber ports at the other of said positions of said valve, whereby liquid admitted to said apparatus through said admission orifice will pass through said pump and discharge through said discharge orifice during both directions of rotation of said pump.

2. An apparatus for pumping liquids comprising a pump casing; a reversible rotary pump therein, one side of said pump being an inlet side for one direction of rotation and a discharge side for theother direction of rotation of said pump, and the other side of said pump simultaneously respectively being a discharge and an inlet side; a valve chamber; and a piston valve in said chamber axially movable to two opposite positions, said chamber providing with said valve'at each end thereof a space for valve-operating liquid and said spaces being in communication with said casing, each at one of said sides of said pump to effect movement of said valve by pump-produced liquid pressure to one or the other of its said positions dependently responsive to the direction of rotation of said pump, said-valve being moved in a direction from, and by the liquid in, the space in communication with the then discharge side of said pump, said chamber having four axially spaced consecutively arranged ports, the two end ports being in communication with said casin at either of said outlet port openings to said disat one side of said pump and the two intermediate ports being in communication with said casing at the opposite side of said pump, one end port and its adjacent intermediate port being inlet ports and the other ports being outlet ports, said chamber further having an admission orifice transversely opposite said inlet ports and a discharge orifice transversely opposite said outlet ports, said valve having a port for controllably opening said inlet ports and opening transversely throughsaid valve at either of said inlet port openings to said admission orifice, said valve further having another port for controllably opening said outlet ports and opening transversely through said valve at either of said outlet port openings to said discharge orifice, said two valve ports being operatively independent of said two end spaces and liquid-pressure balanced in an axial direction, rendering said valve movably unaflected by the liquid passing through said valve ports, said four chamber ports being suitably positioned in said chamber and said two valve ports being suitably positioned in said valve to effect opening of two alternately disposed chamber ports and closing of the other two chamber ports at one of said positions of said valve, and opening of the other two alternately disposed chamber ports and closing of the remaining two .chamber ports at the other of said positions of said valve, whereby liquid admitted to said apparatus through said admission orifice will pass through said pump and discharge through said discharge orifice during both directions of rotation of said pump.

' GEORGE A. MUELLER, JR.

RALPH J. HOOKER. JOHN W. ANDERSON. 

